text: // Copyright (c) Microsoft Corporation.
  // Licensed under the MIT license.
  /**
   * Tests an object to determine whether it implements TokenCredential.
   *
   * @param credential - The assumed TokenCredential to be tested.
   */
  export function isTokenCredential(credential) {
      // Check for an object with a 'getToken' function and possibly with
      // a 'signRequest' function.  We do this check to make sure that
      // a ServiceClientCredentials implementor (like TokenClientCredentials
      // in ms-rest-nodeauth) doesn't get mistaken for a TokenCredential if
      // it doesn't actually implement TokenCredential also.
      const castCredential = credential;
      return (castCredential &&
          typeof castCredential.getToken === "function" &&
          (castCredential.signRequest === undefined || castCredential.getToken.length > 0));
  }
  //# sourceMappingURL=tokenCredential.js.map